In my opinion i would paint the models the same way as the black legion, but keep one shoulder pad the original colour with the legion-specific badge on it. I saw this done somewhere but can't remember where, and it looked quite good :yes:. Plus it would keep the army looking coherant whilst units can be identified easily on the battlefield. Not sure how you could do it on a vehicle (If you want legion specific vehicles that is) possibly painting the doors in the original legion colours?
__________________  |